NVIDIA, Google, and Microsoft push 800 VDC into AI data centers through OCP, targeting 2 MW per rack row by 2027

NVIDIA, Google, and Microsoft published a joint 800 VDC white paper through the Open Compute Project in March 2026 and followed it with the LVDC Solid-State Transformer Specification v0.3 in July 2026^[1]. More than 80 equipment manufacturers and infrastructure companies are already building products to the specification, and the first MGX-compatible 800 VDC power racks are in production with shipments expected in the second half of 2026.

Why 48 V no longer works

Traditional data centers ran server racks at roughly 15 kW using 48 V power distribution. AI has broken that model. AI-focused racks can now reach 200-600 kW, with requirements potentially approaching 1 MW per rack within the next two to three years. Delivering 600 kW at 48 V would require roughly 12,500 A of current - a volume of copper cabling and busbars that is physically and economically impractical.

The problem compounds at every conversion stage. Legacy architectures route power through a UPS, a power distribution unit, and then step it down to 48 V before it reaches the rack - three to four conversion stages in total, each one bleeding energy as heat^[1]. As Keysight Technologies product manager Steven Lee put it, the fewer stages between the grid and the GPU, the better the overall efficiency^[1].

The 800 VDC architecture

The shift to 800 VDC collapses the conversion chain. Solid-state transformers can convert medium-voltage AC directly to 800 V DC, replacing the traditional iron-core transformer and the separate AC-to-DC rectifier with a single stage^[1]. From the 800 V DC bus, a second stage steps down to sub-1 V GPU core voltage. Texas Instruments demonstrated this two-stage path at NVIDIA GTC in March 2026, reporting 97.6% peak efficiency and power density above 2,000 W/in³ for its GaN-based 800 V-to-6 V converter.

Wide-bandgap semiconductors are central to making this work:

• SiC handles the highest voltages and power loads in the front-end conversion, with superior thermal performance enabling next-generation SST designs^[1].
• GaN enables faster switching in intermediate bus converters, raising power density and cutting switching losses^[1].
• PMICs manage the final point-of-load conversion to the sub-1 V rails that GPUs and AI accelerators require^[1].

Infineon joined NVIDIA's MGX AI Factory ecosystem in May 2026, positioning its SiC and GaN portfolio across the full power chain from grid to processor. SolarEdge and Infineon are jointly developing a modular 2-5 MW SST building block targeting medium-voltage to 800-1,500 V DC conversion at greater than 99% efficiency, with customer evaluation units planned for 2027.

NVIDIA's three-stage rollout

NVIDIA has outlined a phased implementation path:

1. 800 VDC power rack (H2 2026) - an MGX-compatible hybrid unit that integrates with existing AC infrastructure without changes to a building's electrical system.
2. Row power center (2027) - a centralised power station using an overhead 800 VDC busway, supporting up to 2 MW per rack row.
3. DC power block (greenfield) - facility-scale conversion from grid power directly to 800 VDC for new builds.

Infineon's Peter Wawer, speaking at PCIM 2026, described the rack power trajectory: roughly 125 kW today, stepping to 500 kW, then to 1 MW as the 800 V high-voltage DC-DC architecture matures^[1].

The safety and standards layer is still catching up. DC arcs cannot self-extinguish at zero crossings the way AC arcs do, insulation requirements in liquid-cooled environments are more demanding, and global safety certification frameworks for 800 VDC have not yet fully converged. OCP's Diablo 400 specification and the EMerge Alliance are driving standardisation, but operators making infrastructure decisions now are locking in choices that will either support or constrain the 2027-2030 hardware cycle - electrical distribution equipment does not get replaced casually. The pace at which SiC and GaN device costs continue to fall, driven partly by the mature 800 V EV supply chain, will determine how quickly the economics tip decisively toward the new architecture.